pdf

First check whether the PDF has fillable fields using pypdf's get_fields method. For fillable forms, extract field info to JSON, map values to field IDs, and write them with PdfWriter. For non-fillable PDFs, add FreeText annotations at computed coordinates.

Use pdfplumber's extract_tables method, which detects cell boundaries and returns rows as lists. You can convert results to pandas DataFrames and export to Excel, with custom table settings for complex layouts.

pypdf handles structural operations like merging, splitting, rotating, encryption, and form field updates. pdfplumber focuses on content extraction with precise coordinates, making it better for text layout analysis and table detection.

Scanned PDFs contain images rather than text layers, so standard parsers return nothing. Convert pages to images with pdf2image, then run OCR with pytesseract to recover the text content.

ReportLab's built-in fonts lack Unicode subscript and superscript glyphs, so those characters render as solid boxes. Use the <sub> and <super> XML markup tags inside Paragraph objects instead.

Extract text labels, lines, and checkbox coordinates with pdfplumber-based structure extraction, or estimate positions visually from rendered page images. Then validate bounding boxes and add FreeText annotations at those coordinates with pypdf.